Islamabad: An American UN worker held hostage for two months is heading home, a day after he turned up unharmed, lying alongside a road in western Pakistan with his hands and feet bound.

UN spokeswoman Jennifer Pagonis said Solecki left the country on a special medical flight early on Sunday morning after spending the night in a military hospital in Quetta.

She said "he seemed OK this morning" and was looking forward to being reunited with his family, but declined to offer further details.

Interior Minister Rehman Malik said Solecki would fly to Bagram Airfield in Afghanistan and then continue on to the United States.

Solecki, who headed the UN refugee agency's operations in Quetta, made no public comment. Police and UN officials declined to discuss what led to his release.